The graph below shows the results of an experiment in which mice learned to run through a maze.
Which was the control group and which was the experimental?
Why was a control group needed?

Verified step by step guidance

1. Examine the graph carefully: The graph shows two groups of mice, one labeled 'No reward' (red line) and the other labeled 'Food reward' (blue line). The y-axis represents the average time to complete the maze in minutes, while the x-axis represents the days of the experiment.
2. Identify the control group: The 'No reward' group is the control group because it represents the baseline condition where no external incentive (food reward) is provided to influence the mice's behavior.
3. Identify the experimental group: The 'Food reward' group is the experimental group because it is subjected to a specific condition (food reward) to test its effect on maze completion time.
4. Explain the need for a control group: A control group is essential to provide a comparison against the experimental group. It helps determine whether the observed changes in maze completion time are due to the food reward or other unrelated factors.
5. Interpret the results: The graph shows that the mice in the 'Food reward' group progressively reduced their maze completion time more significantly than the 'No reward' group, suggesting that the food reward positively influenced their learning and performance.

Key Concepts

Control Group

The control group in an experiment is the group that does not receive the treatment or intervention being tested. In this case, the mice that ran the maze without a food reward represent the control group. This allows researchers to compare the results against the experimental group, which receives the treatment (food reward), to determine the effect of the treatment.

Experimental Group

The experimental group is the group in an experiment that receives the treatment or intervention. In this scenario, the mice that were given a food reward after completing the maze constitute the experimental group. This group is essential for assessing how the treatment influences behavior or performance compared to the control group.

Importance of Control Groups

Control groups are crucial in scientific experiments as they provide a baseline for comparison. They help to isolate the effects of the independent variable (in this case, the food reward) on the dependent variable (maze completion time). Without a control group, it would be difficult to determine whether any observed changes in the experimental group were due to the treatment or other external factors.